The slide of the new Milton-Madison Bridge is now under way. The nearly half-mile steel truss is being slid laterally 55 ft onto refurbished permanent piers. While there have been reportedly more than 30 bridge slides in the U.S., the Milton-Madison Bridge will be the longest steel truss (2,428 ft) in North America to be slid laterally into place.
Once the bridge—across the Ohio River between Madison, Ind., and Milton, Ky.—is moved onto its permanent piers, it will take approximately a week to complete inspections, road connections to the bridge and other work, which means the bridge will remain closed until mid-April.
Additional restraints were installed and the sliding harnesses modified as part of the prep work. This additional work followed a four-step process: The measures were designed off-site, the designs were reviewed by the states, the materials were fabricated and/or delivered to the site and they were installed by bridge crews.
Each of the four steps had its own timeline, and one must be completed before the next. “We’re working diligently and carefully to move the bridge and get it reopened safely and in a timely manner,” said Kevin Hetrick, project manager for the Indiana Department of Transportation (INDOT).
Structural engineers will continue to monitor and inspect the bridge throughout the process to ensure it is safe through all phases of work. Meanwhile, Walsh Construction crews continue to work as they are able on other tasks that must be completed before the bridge reopens to traffic, such as installing the remaining concrete railings and deck for the Indiana and Kentucky approaches to the bridge.
Last month construction crews completed the job of jacking up the bridge and replacing a steel bearing that dislodged March 11. The southeast corner of the bridge was raised nearly a foot in order to slide the bearing into place. The jacks were then removed, placing the bridge load back on its bearings.
On March 13, a 100-foot concrete approach bridge section was slid laterally into place over the Milton, Ky., riverbank. This was a precursor of the upcoming main truss slide because it involved the same equipment and process. Time-lapse video is available on the project website’s News Center page: http://www.miltonmadisonbridge.com/news-center/.
As updates become available, they will be posted on the project’s website, http://www.miltonmadisonbridge.com, and via Twitter @mmbridgeproject.
The Milton-Madison Bridge Project is a joint effort between the Indiana Department of Transportation and Kentucky Transportation Cabinet. The new steel truss bridge is 2,428 ft long and 40 ft wide with two 12-ft lanes and 8-ft shoulders—twice as wide as the old bridge.
